WASHINGTON — As al-Qaida is weakened by the loss of leaders, fighters, funds and ideological appeal, the extremist network’s ability to attack targets in the U.S. and Western Europe has diminished, anti-terrorism officials say.

Nonetheless, al-Qaida and allied groups based primarily in Pakistan remain a threat, particularly because of an increasing ability to attract recruits from Central Asia and Turkey to offset the decline in militants from the Arab world and the West.

Al-Qaida’s relative strength these days is of critical importance in the complex debate in Washington over future U.S. troop levels and tactics in Afghanistan and Pakistan. Although factions within the Obama administration differ on how best to deal with the Taliban in Afghanistan, all agree the paramount priority is defeating al-Qaida. Unlike the Afghan Taliban, al-Qaida remains committed to a holy war on the West with a goal of matching or surpassing its devastating attacks in 2001.

Western intelligence officials say that the group, already under pressure from U.S. drone strikes and facing a likely Pakistani army assault on its sanctuary, has been further racked by internal division and rifts with Pakistani tribal groups.

“Some pretty experienced individuals have been taken out of the equation,” a senior British anti-terrorism official said in a recent interview.

“There is fear, insecurity and paranoia about individuals arriving from outside, worries about spies and infiltration,” said the official, who requested anonymity because of the sensitive topic. “There is a sense that it has become a less romantic experience. Which is important because of the impact on al-Qaida the brand, the myth, the idea of the glorious jihadist.”

Al-Qaida has failed to strike the United States during the last eight years and last spilled blood in the West in July 2005, when bombing attacks on the London transportation system killed 52 people. Global cooperation and aggressive infiltration by Western spy services have thwarted subsequent plots, and a stepped-up campaign of drone strikes in northwestern Pakistan has killed many al-Qaida leaders and intensified divisions among extremist groups.

Tense times

“There are tensions about AQ as an entity,” the British official continued. “It has embedded itself in (northwestern Pakistan) over the course of years with marriages, links to tribes. The drone strikes appear to be straining those bonds with the locals.”

Arabs and Westerners still trek to the training compounds of Waziristan, although their numbers have shrunk as intelligence services get better at tracking and capturing trainees. British militants thought to have trained in Pakistan during the last year and a half number in the tens, not the hundreds, the official said.

“Is (northwestern Pakistan) becoming a less congenial place to undertake jihadist terror training?” the official said. “If so, what do they do? Do they decide it is better to look elsewhere, someplace like Somalia, where many are going, or stay at home?”

French authorities say only small numbers of militants from France are going to Pakistan. Italian anti-terrorism officials have not detected any recruits from Italy traveling to Pakistan since 2005 or 2006, said Armando Spataro, a top terrorism prosecutor in Milan.

The dwindling supply of foreign recruits results partly from an ideological backlash in the Muslim world, experts say.

U.S. President Barack Obama cited the debilitated condition of the terrorist network last week during a visit with U.S. counter-terrorism officials. “Because of our efforts, al-Qaida and its allies have not only lost operational capacity, they’ve lost legitimacy and credibility,” he said.

The number of failed plots in the West, whether directed or inspired by al-Qaida, also shows that the quality of operatives has declined, scholar Marc Sageman testified at a hearing of the Senate Foreign Relations Committee last week.

“Counter-terrorism is working,” said Sageman, a former CIA officer and New York Police Department expert. “Terrorist organizations can no longer cherry-pick the best candidates as they did in the 1990s. There is no al-Qaida recruitment program: Al-Qaida and its allies are totally dependent on self-selected volunteers.”

In several recent cases, Western trainees in Pakistan allegedly had contact with Mustafa abu Yazid, also known as Said Sheik, a longtime Egyptian financial boss. Abu Yazid acts as the day-to-day chief of the network while Osama bin Laden and his deputy, Ayman al-Zawahiri, spend their time eluding capture, said the British official.

The training and direction of Westerners have largely been coordinated by one individual: Rashid Rauf, a British Pakistani slain in a missile strike in November. Investigators believe Rauf was the handler of British operatives in plots dating to a failed 2004 bombing in London.

A French trainee who confessed detailed the size and composition of the network to French police this year. Walid Othmani, who is of Tunisian descent, said he trained in the Waziristan region with a mostly Arab contingent of 300 to 500 fighters, according to a French police report provided by a defense lawyer.

Enemy estimates

“The chief of the Arabs is … of Egyptian origin,” Othmani told interrogators. “The Arab group is mostly people of Saudi origin. You find people from the Middle East, North Africans, blacks, Turks and a majority of Arabs.”

Anti-terrorism officials said Othmani’s estimate largely matches previous intelligence.

The French militant also described a trend that may signal a new threat: the rise of Turks and Central Asians.

“There’s a big Turkish group, the Arab group (the smallest of the groups), two rather large Uzbek groups, a group of Uighurs from Turkestan (the region in China officially known as Xinjiang) … the largest of the groups,” he said under questioning. “There are also two Kurdish groups and finally a mixed group led by an Uzbek.”

Western investigators worry about the Uzbek-led Islamic Jihad Union, or IJU. The IJU broke off in 2002 from the Islamic Movement of Uzbekistan, or IMU, a longtime al-Qaida ally. The IJU has made a name for itself as a Turkic-speaking alternative to al-Qaida for Turks and Central Asians. The amount of Internet propaganda produced by the Turkic groups rivals that of al-Qaida and threatens Germany because of its military presence in Afghanistan.

“For the Turkic groups, Germany is America,” said Evan Kohlmann, a terrorism expert who works with law enforcement around the world.